This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The tunable excitation Raman facility has been primarily used for studies of single wall carbon nanotube (SWNT) studies. We have focused on diameter and chirality characterization of a SWNT sample, length characterization of SWNTs, strains in individual SWNTs. Recently, we have started studies on single atomic layer graphene sheets. We are focusing on characterizing the strain in graphene using Raman spectroscopy.